Vane-type rotary pumps



March 28, 1967 E. EICHELE ETAL 3,311,064

VANE-TYPE ROTARY PUMPS Filed July 6, 1964 5 Sheets-Sheet 1 Fig.1 Y I H Jnven/ars EP/CH E/Cl-IELE 7 4L.

March 28, 1967 E. EICHELE ETAL 3,311,064

VANE-TYPE ROTARY PUMPS Filed July 6, 1964 5 Sheets-Sheet 2 Fig. 3

QB I I5 20 March 1967 E. EICHELE ETAL 3,31 4

VANE-TYPE ROTARY PUMPS Filed July 6, 1964 3 Sheets-Sheet 5 United States Patent 10,213 9 Claims. or. 103136) This invention relates to rotary pumps and more particularly to the type which uses a rotor having a series of radially movable vanes therein which sweep the surface of a pump chamber in the course of rotation.

It is an object of the invention to overcome the drawbacks of the prior art by providing a pump of the kind described having a high volumetric efficiency at high pressures and low speeds, as Well as light-weight, compact, and simplified construction.

I It is a further object of the invention to provide a pump which will be economical to manufacture and which will be long lived.

An important feature of the invention resides in the construction in which the rotor is sealed on both sides by means of axially shiftable sealing plates exposed to pressure on their outer surfaces so as to be flexed into full and sealing contiguity with the rotor, and thus afford a high degree of sealing in order to achieve high volumetric efliciency.

It is another feature of the invention to provide a construction in which no rotating part of the pump comes into actual contact with the pump housing, such effect being achieved by the use of a ring within the housing having an oval opening in which the rotor rotates and thus affording a pair of pumping chambers. The construction is such that the ring and the sealing plates are maintained stationary, the sealing plates being centered in large bores in the housing so as to accurately locate the rotor shaft in true axial alignment, by virtue of providing for support of the rotor shaft in one of the end plates through which it passes.

Additionally, the end plates, subjected to outlet pressure on their outer faces, are of different area so that there is a constant bias toward one end of the housing especially designed to support the axial force by means of an internal shoulder in the housing against which the smaller end plate bears. Such construction is advantageous for the reason that housing is used for the accurately locating and supporting the several elements interiorly thereof, such as the rotor, the sealing plates, and the stator ring, and the co-acting housing surfaces required are thus furnished only at the one end of the housing. The other end of the housing may be closed by a simple cover plate. Such construction provides inherently for a simplified coring and channelling as well as recessing of the housing casting for the several passages required for fluid being pumped. Further, the arrangement permits the use of a light metal for the housing.

With regard to the sealing plates which press on each side of the rotor by action of the outlet pressure, the flexibility of such plates may be increased by tapering them so that they are thicker at the centers than at their peripheries. Flexing depends upon the modulus of elasticity of the sealing plate material and is a matter of choice and design. Any suitable material capable of flexing within the pressure range of the pump may be use for example, metal. Further, by providing for the radial tapering of the plates, it is possible to regulate the amount of flexing of each plate so that one plate is capable of flexing more than the other, a feature which may be taken advantage of in various applications. Thus, the outer portions of the plates will flex more than the center portions and the plates will, accordingly, fit themselves very accurately to the rotating elements within the stator ring.

A further advantageous feature of the construction is the provision of means for centering the stator ring by the use of arcuate spacers between the collar and the housing bore in which it is carried. Such construction eliminates the need for through dowels or pins and the boring required for such elements, a considerable saving in construction costs.

A detailed description of the invention now follows in conjunction with the appended drawing in which:

P18. 1 is an axial cross-sectional elevation of the invention.

FIG. 2 is a section through IIII of FIG. 1.

FIG. 3 is a section through III-III of FIG. 2.

FIG. 4 is a section through IVIV of FIG. 2.

FIG. 5 is a section through VV of FIG. 1.

Referring to the drawing, there is shown a housing 1 which may be a casting, and into which passes a rotor driving shaft 2 for the ump rotor 3 carrying a series of vanes 5 in respective slots 4, in angular array in the usual manner. The shaft 2 is extended to pass substantially through entire rotor bore 76 and provides support therefor on extension 74.

The rotor revolves in a stator ring 6 which is nonrotatively fixed in the housing in a manner to be described and which has an oval opening as shown in FIG. 2 wherein the smaller diameter substantially matches the rotor diameter and which provides a pair of pumping chambers in which the peripheral Walls effect reciprocal movement of the vanes in a well understood manner. The shaft is carried in a ball bearing 19 and is further supported in a bore 71 of a sealing plate 7 which plate bears against one side of the rotor and has a periphery 9 carried in an accurately machined bore 11 of the housing to thus center the shaft. A seal 22 is provided to seal the periphery of plate 7 with respect to the housing.

An additional sealing plate 8 is provided on the other side of the rotor and has a periphery sealed in the housing bore by the seal 23. A through pin 29 passes through plate 8, stator ring 6, and plate 7, socketing in bore 29 of the housing, whereby the plates and the stator ring are maintained relatively rotatively stationary.

It will be noted that plates 7 and 8 have axial movement freedom, relative to their respective pressure chambers 17 and 18, although biased unidirectionally toward shoulder 32 as later explained. Likewise the rotor and stator ring have some axial movement freedom so that plate 7 may be maintained in abutment with shoulder 32 of the housing 1.

Although not shown on the drawing, it will be understood that the sealing plates 7 and 9 are thicker at their centers and are provided with a suitable degree of taper toward their peripheries so as to effect flexing due to pressure on their exterior faces 13 and 14, respectively. Such pressure is effected by outlet pressure in the chamber 17 which comprises the end wall 15 of the housing, for plate 7, and in the chamber 18, which is closed by the housing cover 16, for plate 8. Cover 16 is sealed in the housing as by the sealing ring or gasket 24.

The shaft is further sealed against leakage by the sealing device 56 of a conventional construction and the plate 7 is further sealed by the seal ring within the inwardly extending collar 28 of the housing and the extending collar 27 of plate 7.

Sealing ring 7 bears, at its surface 72, against the rotor 3 and stator ring 6, and the sealing plate 8 has a similar bearing surface on the other side of the rotor and stator ring, as will be apparent from FIGS. 1, 3 and 4; It will be understood that both of the sealing plates 27 and the seal 25 therebetween.

are axially shiftable and, as seen in FIGS. 3 and 4,

-springs 20 are furnished in bores 20' to effect a bias on plate 8, rotor 3 and stator ring 6, and plate 7 so that as understood from FIGS. 1 and 4, these components are supported bythe shoulder 32 of the housing. An annular spacing 21 is provided between the stator ring 6 and the interior bore of the housing and this is .a-suction channel which feeds fluid to be pumped from an inlet 21, FIG. 2, via suction chambers 42 and 42', which feed the respective crescent-shaped pumping chambers of the stator ring. Each such crescent-shaped chamber has a suction region and a pressure region. Thus, as seen on FIG. 2, the two suction regions are 40 and 40 and the two pressure regions are 41 and 41 andv such regions are, of course, separated by the moving vanes. The pressure or outlet regions connect to a pump outlet 17 via the pressure chamber 17. Thus, the plates 7 and 8 have two channels 45 and two channels 46 respectively which communicate with the outlet pressure regions 41 and 41, respectively, (FIG. 2). Channels 46 in plate 8 connect both of the pressure regions 41and 41 with the pressure chamber 13 as well aswith the pressure chamber 17 via a channel 49 in the stator collar 6.: Accordingly, pressure is fed to the outlet 17" which has direct connection with chamber 17 as mentioned above.

Further, the. pressure fluid is conducted from chamber 18 .by means of bores 52 and annular groove 53, these passagesbeing provided in plate 8, to the bottom portions 54 of the vane slots 4. The fluid pressure thus acts on the. vanes topress them outwardly against the inner, oval surface of the stator ring 6.

It will be noted that the stator ring 6 is bevelled at its side margins 26 and 26, FIG. 1, for that portion which is adjacent the suction chambers 42 and 42' (FIG. 1) in order to-facilitate entrance of fluid from annular suction channel 21 to the suction regions 40 and 40'.

Thus, the chambers 17 and 18 are provided with outlet pressure, and it will be noted that the outer face of platen8 is exposed in greater area to such pressure than is the corresponding face of plate 7 due to the collar'extension 28 (FIG. 1) and the collar extension Thus, the inner area of the, plate is cut off for the radial area of the collar I extension 27 whichreduces the area on which the pressure in chamber 17 can act on that area designated as 13 in FIG. 1. Accordingly, a pressure differential exists, biasing the plates and stator..ring and rotor toward the shoulder32 in order to maintain a desirably close fit between these several parts which is important for high speeds; However, a further important effect of the ditferential'pressure provided is the elimination of any specially close-fitting parts at the other end of the rotor in conjunction with the housing cover 16.

The end 59 of the shaft 2 is exposed in a clearance space 60 provided by the central portion of plate 8, FIG. 1, and such clearance space connects by, means of the axial bore 68 and radial bore 67 and annular groove '65 to slanted bore 66 to the annular suction chamber 21 so asto prevent any axial play of the shaft which might otherwise be effected by fluid under outlet pressure finding its way to the shaft end 59, thus avoiding axial thrust.

Theseal 56, in conjunction with the seal 25, effects a recess 57, intermediate seal 56 and the face 58 of the extending collar 27 of plate 7. The recess 57 is likewise relieved of any possible leakage of outlet pressure by grooves 65 connecting to the annular groove 69. The

. construction provides for the extended portion 73 of the shaft 2 and the further extended portion 74 to give excellent support for the rotor as well as bearing support in the plate 7. The portion 74 of the shaft is provided with key means for keying to the rotor for drive thereof. Any conventional key arrangement, as heretofore known, may be used.

A suitable pressure and discharge regulating valving arrangement may, of course, be used in conjunction with the pump described.

The stator ring 6 may be supported in the housing, as seen in FIG. 5, by means of arcuate, segmental spacer elements 163 and 194 which may be accurately machined so as to center the stator ring. Thus, such spacer elements have surfaces 106 and 107, respectively, for engagement with the periphery 101 of the stator ring. Accordingly, the usual mode of centering and holding the stator ring, requiring pins or dowels passing through the construction, which dowels must be very accurately located by means of bores precisely disposed, is eliminated, and the construction of the pump made relatively economical from this standpoint.

In summation of operation, assuming there is no pressure in the pump, the springs 20 will maintain the several contiguous elements biased against the shoulder 32.

When the pump is running, the rotating vanes cause a suction which will bring in fluid through opening 21', from whence it will be conducted from the annular suction chamber 21 and the suction recesses 42 and 42' to the suction regions of the pump chambers and 40. The pump action then forces the fluid to the respective pressure regions 41 and 41' and thence out through the respective channels and 46 of plates 7 and 8 to the pressure chambers 17 and 18 at the exterior faces of the respective plates. From these chambers the fluid passes to the outlet opening 17 which is directly connected to chamber 17.

The pressure in the chambers 17 and 18, acting on the sealing plates, will flex the plates against the respective rotor and stator ring sides and also against the edges of the vanes to the extent that they are permitted to do so by the plate material flexibility and the clearance or tolerance provided for the vane edges with respect to the axial dimension of the rotor. Such flexing can, of course, be controlled as a matter of design, depending upon the material of the plates, the pressures involved, and the dimensioning of the plates. Volumetric efficiency for the construction is fairly constant for a large range of pressures due to the effective sealing provided.

We claim:

1. In a pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said rotor and stator ring having axial freedom, said stator ring having walls surrounding said rotor and effecting pump chamber means therefor, and means rotative ly mounting said rotor, a sealing plate on each side of said rotor and stator ring within said housing, said plates being independently axially movable relative to said rotor and stator and each plate having a side contiguous with said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet passages connecting the pump chamber means with said pressure chamber means whereby fluid pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, and shoulder means in said housing against which one of said plates abuts, and means for providing a diflerential bias on said plates to effect a force against said rotor and stator ring to said one plate to effect abutment thereof against said shoulder means.

2. In a pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said rotor and stator ring having axial freedom, said stator ring having walls surrounding said rotor and efiecting pump chamber means therefor, and means rotative ly mounting said rotor, a sealing plate on each side of said rotor and stator ring within said housing, said plates being independently axially movable relative to said rotor and stator and each plate having a side contiguous with said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet passages connecting the pump chamber means with said pressure chamber means whereby fluid pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, and shoulder means in said housing against which one of said plates abuts, and means for providing a bias on the other of said plates to effect a force against said rotor and stator ring to said one plate to effect abutment thereof against said shoulder means, said means for providing said bias comprising springs engaging said other plate.

3. In a pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said rotor and stator ring having axial freedom, said stator ring having walls surrounding said rotor and effecting pump chamber means therefor, and means rotatively mounting said rotor, a sealing plate on each side of said rotor and stator ring within said housing, said plates being independently axially movable relative to said rotor and stator and each plate having a side contiguous with said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet passages connecting the pump chamber means with said pressure chamber means whereby fluid pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, and means for providing differential areas of said plates exposed to outlet pressure in respective outlet pressure chamber means, wherein one plate has a larger area exposed to outlet pressure to bias said plates unidirectionally into abutment with said housing.

4. In a pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said rotor and stator ring having axial freedom, said stator ring having walls surrounding said rotor and effecting .p-umpchamber means therefor, and means rotatively mounting said rotor, a sealing plate on each side of said rotor and stator ring within said housing said plates being independently axially movable relative to said rotor and stator and each plate having a side contiguous with said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet passages connecting the pump chamber means with said pressure chamber means whereby fluid pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, and shoulder means in said housing against which one of said plat-es abuts, and means for providing a differential bias on said plates to effect a force against said rotor and stator ring to said one plate to effect abutment thereof against said shoulder means, said means for providing said differential bias comprising a collar of said housing and a collar of said one plate, one collar extending into the other, and sealing means intermediate said collars whereby the radial area of said one plate is diminished by the area bounded by the periphery of the collar thereof, said rotor having a shaft passing through said collars and terminating short of said other plate.

5. In a pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said stator ring having walls surrounding said rotor and effecting pump chamber means therefor, a sealing plate on each side of said rotor within said housing, said plates being independent-1y axially movable and each plate having a side contiguous with said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet, passages connecting the pump chamber means with said pressure chamber means whereby outlet pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, and shoulder means in said housing against which one of said plate abuts, and means for providing differential areas of said plates exposed to outlet pressure -to effect a net force whereby said one plate abuts against said shoulder means.

6. In a pump of the kind described, a housing having an annular chamber and a stator ring fixed in said chamber and having a rotor therein and effecting pump chamber mean therefor, means for supporting and rotating said rotor, arcuate spacer elements for locating and supporting said stator ring in said annular chamber disposed in said annular chamber and engaging said stator ring and spacing said stator ring from walls of said annular chamber to effect a suction channel, said housing having an inlet and said suction channel communicating therewith, said arcuate spacer elements being smaller in axial dimension than said suction channel to permit flow therearound.

7. In a pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said rotor and stator ring having axial freedom, said stator ring having walls surrounding said rotor and effecting pump chamber means therefore, and means rotatively mounting said rotor, a sealing plate on each side of said rotor and stator ring within said housing, said plates being independently axially movable relative to said rotor and stator and each plate having a side contiguous with said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet, passages connecting the pump chamber means with said pressure chamber means whereby fluid pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, said plates being thinner at their peripheries than at their center portions so as to flex to a greater extent at their peripheries toward said stator ring to effect a close sealing co-action with said stator ring,and shoulder means in said housing against which one of said plates abuts, and means for providing a bias on the other of said plates to effect a force against said rotor and stator ring to said one plate to effect abutment thereof against said shoulder means, said means for providing said bias comprising springs engaging said other plate.

'8. In a pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said rotor and stator ring having axial freedom, said stator ring having walls surrounding said rotor and effecting pump chamber means therefor, and means rotatively mounting said rotor, a sealing plate on each side of said rotor and stator ring within said housing, said plates being independently axially movable relative to said rotor and stator and each plate having a side contiguous with said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet, passages connecting the pump chamber means with said pressure chamber means whereby fluid pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, said plates being thinner at their peripheries than at their center portions so as to flex to a greater extent at their peripheries toward said stator ring to effect a close sealing co-action with said stator ring, and means for providing differential areas of said plates exposed to outlet pressure in respective outlet pressure chamber means, wherein one plate has a larger area exposed to outlet pressure to bias said plates unidirectionally into abutment with said housing.

a 9. In a'pump of the kind described, a housing having an inlet and an outlet, a stator ring in said housing and having a rotor therein and said rotor and stator ring having axial freedom, said stator ring having walls surrounding said rotor and effecting pump chamber means therefor, and means rotatively mounting said rotor, a sealing plate on each side of said rotor and stator ring within said housing, said plates being independently axially movable relative to said rotor and stator and each plate having a side contiguous With said rotor and said stator ring, a pressure chamber means on each of the other sides of said plates and said pressure chamber means being connected to said housing outlet, passages connecting the pump chamber means with said pressure chamber means whereby fluid pressure is exerted on said plates to press said plates against said rotor and stator ring for sealing of said pump chamber means in said stator ring, said plates being thinner at their peripheries than at their center portions so as to flex to a greater extent at their peripheries toward said stator ring to efiFect a close sealing co-action with said stator ring, and shoulder means in said housing against which one of said plates abuts, and means for providing a bias on the other of said plates to eifect a force against said rotor and stator ring to said one plate to effect abutment thereof against said shoulder means, said means for pro- 8 Vidiflg said bias comprising springs engaging said other plate, and means for providing differential areas of said plates exposed to outlet pressure in respective outlet pressure chamber means, wherein one plate has a larger area exposed to outlet pressure to bias said plates unidirectionally into abutment with said shoulder means.

References Cited by the Examiner UNITED STATES PATENTS 2,384,872 9/1945 Baker et a1. 103-126 2,544,988 3/1951 Gardiner et a1. 103-135 2,918,873 12/1959 =Erdmann 103-136 2,924,182 2/ 1960 Blasutta 103-136 2,941,479 6/1960 Rosaen 103-136 3,034,447 5/1962 Brundage 103-126 3,073,251 1/1963 Weigert 103-126 3,097,610 7/1963 Swanson 103-136 3,106,897 10/1963 Johnson 103-126 3,187,678 6/1965 Pettibone 103-136 3,198,127 8/1965 Brundage 103-136 3,204,566 9/1965 Feroy 103-136 DONLEY J. STOCKING, Primary Examiner.

SAMUEL LEVINE, MARK NEWMAN, Examiners.

R. M. VARGO, W. J. GOODLIN, Assistant Examiners. 

1. IN A PUMP OF THE KIND DESCRIBED, A HOUSING HAVING AN INLET AND AN OUTLET, A STATOR RING IN SAID HOUSING AND HAVING A ROTOR THEREIN AND SAID ROTOR AND STATOR RING HAVING AXIAL FREEDOM, SAID STATOR RING HAVING WALLS SURROUNDING SAID ROTOR AND EFFECTING PUMP CHAMBER MEANS THEREFOR, AND MEANS ROTATIVELY MOUNTING SAID ROTOR, A SEALING PLATE ON EACH SIDE OF SAID ROTOR AND STATOR RING WITHIN SAID HOUSING, SAID PLATES BEING INDEPENDENTLY AXIALLY MOVABLE RELATIVE TO SAID ROTOR AND STATOR AND EACH PLATE HAVING A SIDE CONTIGUOUS WITH SAID ROTOR AND SAID STATOR RING, A PRESSURE CHAMBER MEANS ON EACH OF THE OTHER SIDES OF SAID PLATES AND SAID PRESSURE CHAMBER MEANS BEING CONNECTED TO SAID HOUSING OUTLET PASSAGES CONNECTING THE PUMP CHAMBER MEANS WITH SAID PRESSURE CHAMBER MEANS WHEREBY FLUID PRESSURE IS EXERTED ON SAID PLATES TO PRESS SAID PLATES AGAINST SAID ROTOR AND STATOR RING FOR SEALING OF SAID PUMP CHAMBER MEANS IN SAID STATOR RING, AND SHOULDER MEANS IN SAID HOUSING AGAINST WHICH ONE OF SAID PLATES ABUTS, AND MEANS FOR PROVIDING A DIFFERENTIAL BIAS ON SAID PLATES TO EFFECT A FORCE AGAINST SAID ROTOR AND STATOR RING TO SAID ONE PLATE TO EFFECT ABUTMENT THEREOF AGAINST SAID SHOULDER MEANS. 